‰  NOW 13 WPM  ‰  TEXT IS FROM APRIL 2017 QST  PAGE 41  ‰

INDICATING THAT THE FEED LINE WAS NOT RESONANT, AND THEREFORE NOT AFFECTING
THE MEASURED PERFORMANCE.  THIS TEST WAS WITHOUT A BALUN, WHICH I
NEVERTHELESS INSTALLED WHEN MOUNTING THE ANTENNA.  THE ARRL ANTENNA BOOK
SHOWS A CHOKE BALUN FOR THEIR RECTANGULAR LOOP.  I USED THREE TURNS OF RG 8
ABOUT 6 INCHES IN DIAMETER, ALONG WITH ONE CLAMP ON FERRITE BEAD TO KILL
THE Q IF ANY RESONANCES SHOW UP.  USING THESE PRECAUTIONS EVEN WHEN TESTING
IS A GOOD IDEA TO GET THE BEST DATA.  ALTERNATE TUNING METHODS IF YOU
ƒ  QST DE W1AW  ‰
PREFER, YOU CAN MAKE BOTH LOOPS IDENTICAL AND RESONATE THEM INDIVIDUALLY AT
50R2 MHZ.  THEN YOU CAN ADD 50 OF REACTANCE IN SERIES WITH EACH LOOP.  ONE
LOOP SHOULD HAVE 65 PF IN SERIES WITH IT, THE OTHER A COIL OF 166 NH, WHICH
IS ABOUT FOUR TURNS 1/2 INCH IN DIAMETER AND 1/2 INCH LONG.  MEASURE BOTH
COMPONENTS WITH AN RF BRIDGE TO ACCOUNT FOR PARASITIC EFFECTS AND ADJUST
EACH AS CLOSE TO 50 REACTANCE AT 50R2 MHZ AS YOU CAN.  THEN CONNECT THE TWO
‰  END OF 13 WPM TEXT  ‰  QST DE W1AW  ƒ